Freezing compartment structure



Sept. 4, 1951 w. G. KOGEL FREEZING COMPARTMENT STRUCTURE 2 Sheets-Sheet1 Filed Jan. 27, 1948 1 4, 1951 w. G. KOGEL FREEZING COMPARTMENTSTRUCTURE 2 Sheets-Sheet 2 Filed Jan. 27, 1948 D NVEN 0R. J g 4 PatentedSept. 4, 1951 FREEZING COMPARTMENT STRUCTURE Wilhelm Georg Kiigel,Stockholm, Sweden, as-

slgnor to Aktiebolaget Elektrolux, Stockholm, Sweden, a corporation ofSweden Application January 27, 1948, Serial N o. 4,5i7

In Sweden January 28, 1947 12 Claims. (Cl. 62126) My invention relatesto refrigeration, and more particularly concern transmitting of coolingeffect to different parts of a freezing compartment when the coolingelement of a refrigeration system is associated with the bottom of sucha 5 compartment.

When a cooling element of a refrigeration system is only associated withthe bottom supporting surface of a freezing compartment of adequatedepth to receive ice trays, frozen food packages and other matter to befrozen, cooling effect is readily transmitted to matter which rests directly against the bottom supporting surface. However, difficulty hasusually been encountered in transmitting cooling effect to such matterwhich is stored in the upper part of the freezing compartment and doesnot rest directly against the supporting surface.

It is an object of my invention to provide an improvement fortransmitting cooling-eilect to matter stored in the upper part of afreezing compartment of this type, whereby food products may beeffectively preserved and maintained at a desired low temperature in allparts of the freezing compartment. I accomplish this by providingremovable structure in such a freezing compartment which provides one ormore vertical walls therein and serves as a heat conductor in heattransmitting relation with the bottom supporting surface, whereby suchstructure is capable of transmitting cooling effect to the upper part ofthe compartment when in functioning relationship.

More particularly, I provide a removable structure which forms anenclosure for housing matter to be stored therein, such structure havingspaced apart walls of good heat conducting material which are connectedat their upper parts and in heat conducting relation with the supportingsurface at their lower parts when in functioning re- 40 lation with thesurface, thereby promoting transmitting of cooling effect from thesurface t matter in the upper part of the enclosure.

The invention, together with the upper and other objects and advantagesthereof, will 138*:

more fully understood from the following description taken inconjunction with the accompanying drawings forming a part of thisspecification, and, of which':

Fig. 1 is a front elevation. pattlfbriiken away and in section, of aportion of a refrigerator embodying the'invention;

Fig. 2 illustrates more or less diagrammatically an absorptionrefrigeration system of the inert gas type which may be employed in therefrigerator shown ixfFi'g. l

Fig. 3 is a fragmentary sectional view, taken at line 3-3 of Fig. 1, toillustrate details more clearly;

Fig. 4 is a perspective view of one of the sliding drawers orreceptacles adapted to be positioned in the refrigerator shown in Figs.1 and 3; and

Fig. 5 is a vertical sectional view illustrating a modified form of thedrawers or receptacles shown in Figs. 1 and 3.

Referring to Figs. 1 and 3, I have shown the invention embodied in arefrigerator comprising a cabinet to having an inner metal shell llarranged to be supported within an outer metal shell I2 and insulatedtherefrom with any suitable insulating material The inner metal shelldefine a thermally insulated storage space 15 int which access isafforded by a door Ii hinged to the front of the cabinet. A horizontallydisposed partition I1 is provided in the storage space I 5 to subdividethe space into upper and lower compartments I8 and [9, respectively.

The partition I! comprises a box-like container 20 which is formed ofsuitable sheet metal and is of such size that it extends substantiallyover the entire width of the space I 5 and from the rear wall thereoftoward the open front of the cabinet to a region at which it isrelatively close to the rear face of the cabinet door, when the latteris in its closed position, so that circulation of air between the upperand lower compartments l8 and I9 is substantially prevented. If desired,suitable rails 2| may be provided at the side walls of the inner metalshell II for supporting the container 20.

Evaporator or cooling structure 22 comprising a pair of cooling elements22a and 221), which are in the form of looped coils. are embodied in thecontainer 20. The cooling element 22a is thermally connected to theunderside of the top surface of the container 20 and is primarilyeffective to abstract heat from the upper compartment 18, and thecooling element 22?) is thermally connected to the upper side of thebottom surface of the container and is primarily effective t abstractheat from the lower compartment 19. If

a desired, the container 20 may be filled with a suitable insulatingmaterial 23 for thermally shielding the cooling elements 22a and 22bfrom one another Even when no insulating material 23 isemployed, thestagnant body of air in the container 20 effectively shields the coolingelements 22a and 22b thermally from one another.

The cooling element 22a is adapted to be operated at a lower temperaturethan the cooling element 22b. Since the cooling element 22a is utilizedto effect cooling of the upper compartment 3 it, this compartment may bereferred to as a freezing space adapted to receive ice trays, frozenfood packages and other matter to be frozen. The freezing compartment Itmay be provided with a hinged door 24 at the forward edge of thecontainer 29 which may be spring biased to its closed position in anysuitable manner (not shown) and readily opened by grasping a partthereof. The cooling element 22b is adapted to be operated at a highertemperature than cooling element 22a and is effectively utilized to coolair in the lower compartment l9. If desired, the bottom surface of thecontainer 29 may be provided with fins to provide a relatively extensiveheat transfer surface for effectively abstracting heat from the lowercompartment l9.

The cooling elements 22a and 22b may form the cooling structure of anabsorption refrigeration system of a uniform pressure type, like thatdiagrammatically shown in Fig. 2, in which an inert gas or pressureequalizing fluid is employed. In order to simplify Fig. 2, the coolingstructure 22 has been illustrated in a more or less conventional mannerapart from the refrigerator cabinet illustrated in Figs. 1 and 3. In arefrigeration system of the type shown in Fig. 2 a refrigerant fluid,such as a liquid ammonia, for example, is introduced through a conduit25 into the evaporator structure 22. The refrigerant fluid evaporatesand diffuses in the evaporator structure 22 into an inert gas. such ashydrogen, for example, to produce refrigeration and abstract heat fromthe surroundings.

The resulting gas mixture of refrigerant and inert gas flows from thecooling structure through an outer passage of a gas heat exchanger 26and vertical conduit 21 into an absorber comprising a vessel 29 and alooped coil 29. In the absorber vessel 28 and coil 29 the refrigerantvapor is absorbed by a suitable absorbent, such as water, for example,which is introduced into coil 29 through a conduit 30. The hydrogen orinert gas, which is practically insoluble and weak in refrigerant,returns to the cooling structure 22 from coil 29 through an innerpassage of the gas heat exchanger 25 and a conduit 3|.

From the vessel 29 enriched absorption liquid flows through a conduit 92and inner passage of a liquid heat exchanger 33 into the lower end of avapor lift tube 34 of a generator or vapor expulsion unit 35. Thegenerator unit 35 comprises heating flue 36 havingthe vapor lift tube 34and a boiler pipe 91 in thermal exchange relation herewith, as bywelding, for example. By heating generator unit 35, as by a gas burner38, for example, liquid from the inner passage of the heat exchanger 39is raised by vapor lift action through tube 94 into the upper part ofthe boiler pipe 31. The liberated refrigerant vapor entering boiler pipe31 from the tube 34, and also vapor expelled from solution in the boilerpipe,

, flows upwardly into an air cooled condenser 39 provided with aplurality of heat dissipating members or fins 40. Refrigerant vapor isliquefied in the condenser 39 and returns to the cooling structure 22through the conduit 25 to complete the refrigerating cycle.

The weakened absorption liquid, from which refrigerant vapor has beenexpelled, is conducted from boiler pipe 31 through a conduit 4|, outerpassage of the liquid heat exchanger 99 and conduit 39 into the upperpart of the coil 29. The lower end of the condenser 39 is connected by aconduit 42 to the gas circuit, as to the upper part of absorber coil 29,for example, so that any non- 4 condensable gas which may pass into thecondenser can flow to the gas circuit and not be trapped in thecondenser.

The cooling elements 224 and 22b are connected in series relation withinert gas from conduit 3| flowing upwardly through cooling element 22ain the presence of and in counterfiowto liquid refrigerant which isintroduced through conduit 25. Unevaporated liquid refrigerant isconducted from the lower part of cooling element 22a through a conduit43 from which liquid refrigerant passes into the lower cooling element22b for downward flow in the latter in the presence of and in parallelflow with the inert Since the inert gas flows successively through thecooling elements 22a and 22b, the gas in the upper cooling element 22acontains a lesser amount of refrigerant vapor than the gas in the lowercooling element 22b. The partial vapor pressure of the refrigerant is agradient, so that the temperature of liquid refrigerant in the coolingelements is also a gradient, the evaporating temperature of the liquidbeing lower in the upper cooling element 22a which constitutes thefreezing portion of the cooling structure.

In Figs. 1 and 3 the cooling elements 22a and 22b are in the form oflooped coils each of which is positioned in a single substantiallyhorizontal plane and adapted to extend from one side wall to theopposite side wall of the storage space ii. In order to position thecontainer 20 and cooling elements 22a and 22b therein in the storagespace l5, the rear wall 44 of cabinet I0 is formed with an opening 45defined by a rectangular wooden frame 45. The container 20 forms a partof a cover or closure member 41 for the opening which is arranged tobear against a gasket 48 of suitable insulating material and isremovably secured at 49 to the rear wall 44. The cover 41 contains asuitable insulating materialand parts of the refrigeration systemextend'therethrough which connect the cooling elements with other partsdisposed exteriorly of the cabinet I0.

In accordance with my invention removable heat transfer structure in theform of a number of receptacles or drawers 50 are provided in thefreezing compartment l9 for transmitting cooling effect from the topsurface 5| of the container 20 to the upper part of the compartment. Asbest shown in Figs. 1 and 4, eachreceptacle 50 comprises an inner shellwhich is rectangularshaped in transverse section and includes a flatbottom 52, spaced apart vertically extending walls 53 and a connectingtop 54. The inner shells are formed of material having good heatconducting properties, such as aluminum, for example, and may be shapedfrom metallic sheeting in such manner that the connected edges form alap joint 55 at the top 54.

An outer housing 55 is provided for each receptacle 50 which may beformed of synthetic resinous material or metal, such as aluminum, forexample, and fixed to the inner shell and held in spaced relationtherewith by a number of rivets or studs 51. The studs 51 provide poorheat conducting paths between the inner shells and outer housings 55 ofthe receptacles, and such poor thermal conducting paths, together withthe air gaps 58 formed between these parts, effectively insulate andthermally shield the interiors of the receptacles from the portions ofthe freezing compartment l8 surrounding the receptacles. When thereceptacles 59 are positioned in the freezing compartment ill, the flat5 bottoms 52 are in good thermal contact with the bottom supportingsurface 5! while the lower extremities or edges 5! of the outer housingsii are spaced therefrom, as best seen in Fig. 1.

In order to facilitate the breaking of an ice bond which may be formedbetween the receptacles 50 and the supporting surface 5|, eachreceptacle is provided with a release device comprising a U-shapedhandle having a cross-arm 62 which extends across the front of thereceptacle and parallel side arms 63 which project into the air gap 58and are pivoted at 54 to the outer housing 58. The side arms 63 areformed with .legs 65 which are arranged to bear against the supportingsurface 5| and exert force against the latter when the cross-arm i2 israised upwardly, thereby effectively breaking any ice bond formedbetween the receptacle and the supporting surface and loosening thereceptacle for easy removal from the freezing compartment.

When a receptacle 5| is positioned on the supporting surface 5| of thefreezing compartment II and loaded with ice trays, frozen food packagesor other matter to be frozen, cooling effect is effectively transmittedto the matter resting against the bottom 52 because the latter issubstantially flat and in good thermal contact with the supportingsurface-5|. Since the vertically extending walls 53 are in good heatconducting relation with the supporting surface, cooling effect is alsoefi'ectively transmitted to the matter housed in the upper part of thereceptacles through the walls 53 which essentially serve and act as heatconductors. By providing receptacles ill in which air gaps 58 are formedbetween the inner shells and outer housings 56, the matter stored in thereceptacles is thermally shielded to such an extent from thesurroundings that the matter stored in the upper part thereof can beeffectively maintained at a desired low freezing temperature even whenthe cooling structure of the refrigeration system is only associatedwith the bottom supporting surface of the freezing compartment. In Fig.1 the receptacles 50 take up substantially the entire space across thefreezing compartment l8 and are not only thermally shielded from oneanother but also from the side walls and top of the freezing compartmentby the air gaps of the receptacles.

The advantage just mentioned is realized even when the receptacles 50are open-ended because the vertically extending walls 53 essentiallyform vertical walls which subdivide the freezing compartment l8 into aplurality of spaces alongside of each other between which circulation ofair is restricted. Hence, the walls 53 desirably are of such height thatthey extend for a major portion of the distance from the bottomsupporting surface 5 i to the top of the freezing compartment. In thepreferred embodiment illustrated and just described, the receptacles 50are of optimum height with the vertical walls 53 extending substantiallyfrom the bottom to the top of the freczlng compartment l8, sufficientclearance being provided to enable the receptacles to be readilyinserted into and removed from the freezing compartment as well aspermit operation of the cross-arms B2 of the release devices, as bestshown in Fig. 3.

A further advantage realized is that frozen food packages can be readilyinserted into and removed from the receptacles 50 when the latter havebeen withdrawn from the freezing compartment. Hence, loading of thefreezing compartment is simplified and matter stored at the rear thereofis easily accessible by simply removing a particular receptacle, therebyeliminating the necessity of individually removing a number of frozenpackages directly from the refrigerator and rearranging a considerablenumber of such packages after a particular package sought has beenfound.

If desired, the air gap between the inner shells and outer housings ofthe receptacle 50 may be filled with a suitable insulating material.such as glass wool, for example. Such an embodiment is shown in Fig. 5in which insulating material 86 is retained in the gap between the innershell and outer housing. Further, the inner shells and outer housings ofthe receptacles 5. may be formed to provide a rear wall il havinginsulation therein, as shown in Fig. 5. Such rear wall construction alsomay be embodied in the receptacle first described in which an insulatingair gap is formed between the inner shell and outer housing. When theouter housing is formed of material having poor thermal conductingproperties, such as a synthetic resinous material, for example, theouter housing may overlie and bear directly against the irmer metallicshell.

By way of example and without limitation, a receptacle embodying theinvention which has been found extremely satisfactory was formedentirely of aluminum sheeting, the thickness of the inner shell beingabout 2.5 mm. and that of the outer housing about 0.5 mm. Suchreceptacle is substantially like that shown in Figs. 1 and 4 having anair gap of about 5 mm. between the inner shell and outer housing. Areceptacle of this kind is extremely light and easy to handle andfacilitates loading and unloading of food products and other matter tobe stored in the freezing compartment of a refrigerator. When ice traysfor producing ice are positioned in such a receptacle rather than on anopen shelf of a freezing compartment, the ice freezing time ismaterially reduced. Further, it was found that ice trays and frozen foodpackages and other matter stored in such a receptacle and held fast byan ice bond can be removed more readily than when stored directly in anopen freezing compartment by virtue of the fact that the receptacle andmatter housed therein can be withdrawn from the freezing compartment asa complete unit through the front access opening.

Although I have shown and described my invention in connection with aparticular type of refrigeration system, I do not wish to be limitedthereto since any type of refrigeration system or systems may beemployed to provide a low temperature cooling element for a freezingcompartment of a refrigerator. It will be understood by those skilled inthe art that various changes and modifications may be made withoutdeparting from the spirit and scope of my invention, as pointed out inthe following claims.

What is claimed is:

1. In combination with a household refrigerator comprising a cabinetproviding a freezing compartment having a heat conducting bottomsupporting surface and means to eifect cooling of such surface, saidcompartment having an access opening, of removable structure in saidcompartment which provides one or more vertical walls therein andserving as a heat conductor in heat conducting relation with saidsurface for transmitting cooling effect to the upper part of saidcompartment when in functioning relationship, said structure beinglnsertable into said compartment through the access opening areas-1othereof to position said structure in functioning relationship with saidsupporting surface, and means forming a part of said structure forinsulating said heat conductor from the surroundings in said compartmentwhen said structure is positioned in said functioning rentionship, theexterior surface of said last-mentioned means being in poor heatconducting relation with said heat conductor.

2. For use in a household refrigerator providing a freezing compartmenthaving a, substantial- 1y flat bottom supporting surface and means toeffect cooling of such surface, sush compartment having a front accessopening, removable structure insertable into said compartment at thefront opening to house a plurality of items stacked upon one anotherincluding packaged food products and the like or such products and oneor more ice trays, such items having a poor heat conducting path in anupward direction from said surface to the upper part of saidcompartment, said structure including spaced apart vertically extendingwalls which are connected at their upper parts and in heat conductingrelation with said supporting surface at their lower parts when infunctioning relationship therewith, thereby promoting transmitting ofcooling effect from said surface to items in the upper part of thestructure, and means at the exterior of said spaced apart walls andconnection therebetween for insulating the latter from the surroundingsin said compartment when said structure is nositioned in saidfunctioning relationship, the exterior surface of said last-mentionedmeans being in poor heat conducting relation with said spaced apartwalls.

3. For use in a household refrigerator providing a freezing compartmenthaving a substantially flat bottom supporting surface and means toeffect cooling of such surface, such compartment having a front accessopening, removable structure insertable into said compartment'at thefront opening to house a plurality of food items stacked upon oneanother or such items and one or more ice trays to produce ice cubes,such items having a poor heat conducting path in an upward directionfrom said surface to the upper part of said compartment, said structurebeing constructed and arranged to provide a receptacle defined by abottom and spaced apart vertically extending walls possessing good heatconducting properties which are connected at their upper parts and inheat conducting relation with said supporting surface at their lowerparts when in functioning relation with said surface, and an insulatinghood overlying said receptacle and forming a unitary part of saidstructure for insulating the latter from the surroundings in saidcompart ment when said structure is positioned in said functioningrelationship, the exterior surface of said hood being in poor heatconduct ng relation with the walls of said receptacle.

4. For use in a household refrigerator providing a freezing compartmenthaving a substantially flat bottom supporting surface and means toeffect cooling of such surface, such compartment having a front openingaffording access therein for inserting and removing food products ndother matter, removable structure for housmg such matter when insertedin said compartment, said structure having a height which ex tends for amajor portion of the distance from the supporting surface to the top ofsaid compartment and being constructed and arranged to provide spacedapart vertically extending walls comprising inner members of good heatconducting material which are connected at their upp parts in heatconducting relation with said supporL-sg surface at their lower partswhen in functioning relation therewith, and an outer shell disposedabout said innermembers in poor heat conducting connection therewith.

5. The combination with a refrigerator comprising a cabinet having ahorizontally extending freezing compartment and means to effect coolingof the bottom supporting surface of such compartment, the compartmenthaving a front access opening and closure member therefor, of aplurality of receptacles adapted to be positioned in the compartment tohouse a plurality of items stacked upon one another including packagedfood products and the like or such products and one or more ice trays,such items having a poor heat conducting path in an upward'directicnfrom said surface to the upper part of said compartment, each of saidreceptacles having a height which extends for a major distance from thebottom to the top of the compartment and including spaced apart walls ofgood heat conducting material which are connected at their upper partsand in heat conducting relation with said supporting surface at theirlower parts when in functioning relation therewith, and meanscooperating with said receptacles for insulating the spaced apart wallsthereof from the surroundings in said compartment when said receptaclesare in functioning relation with the supporting surface, the exteriorsurface of the last-mentioned means being in poor heat conductingrelation with said spaced apart walls.

6. For use in a freezing compartment of a refrigerator having means toeffect cooling of the bottom supporting surface thereof, a receptaciefor housing food products and other matter adapted to be positioned onsaid supporting surface, such receptacle comprising an inner metallicshell having a bottom and top and vertical side walls formed of goodheat conducting material, and an outer housing disposed about the topand side walls of said shell in poor heat conducting relation therewith,said housing being out of thermal contact with the supporting surfacewhen the receptacle is positioned thereon.

7. Apparatus as set forth in claim 6 in which said housing is formed ofsheet metal and surrounds the top and side walls of said shell in spacedrelation therewith to provide a narrow gap therebetween, the bottomedges of the portions of said housing overlying said side walls beingspaced from the supporting surface when the receptacle is positionedthereon.

8. Apparatus as set forth in claim 7 in which insulating material isdisposed in the gap between sald sheil and housing.

9. Apparatus as set forth in claim 6 including a device pivotallymounted on sa d receptacle adapted when turned :.0 forcibly loosen thereceptacle from the supporting surface when an ice bond is formedtherebetween.

10. Apparatus as set forth in claim 6 in which said shell is f rmed ofa1um:num and said housing is formed of aluminum and dis sed closelyadjacent to and about the top and side walls 031 said shell, and meansproviding poor heat conducting paths for attaching said housing to saidshell, the b-xwtom edges of the portions of said housing ove-:ying saidside walls being spaced from the supporting :urface when the receptac-eis positione? thereon.

ii. In combination with a refrigerator including a cabinet having afreezing compartment immediately below the top wall thereof, suchcompartment having a front access opening and a substantially flatbottom surface, and cooling means in thermal exchange relation with thebottom surface of said freezing compartment, of removable structurewithin said compartment to promote cooling of food products and othermatter at regions removed from said surface and between which at leastone ice tray may be disposed, said removable structure including one ormore vertical walls and serving as a heat conductor in heat conductingrelation with said surface for transmitting cooling effect to saidreions when in functioning relationship therewith, said structure beinginsertable into said compartment through the access opening to positionsaid structure in functioning relationship, and an insulating outershield for insulating said heat conductor from the surroundings in saidfreezing compartment when said structure is positioned in saidfunctioning relationship, the exterior surface of said shield being inpoor heat conducting relation with said heat conductor.

12. The combination with a refrigerator including a cabinet havingthermally insulated top and spaced apart side walls, a horizontallyextending member having a relatively flat top supporting surface whichis in poor heat conducting relation with the walls of said cabinet, saidmember defining the bottom of a freezing compartment whose top andspaced apart side surfaces are at the immediate vicinities of the topand side walls, respectively, such compartment having a front accessopening and a substantially flat bottom surface, and cooling means inthermal ex- 10 change relation with the bottom surface of said freezingcompartment, of removable structure insertable into said compartment atthe opening to promote cooling of food items stacked upon one another orsuch items and one or more ice trays, such items having a poor heatconducting path in an upward direction from said surface, said structureincluding spaced apart vertically extending walls in heat conductingrelation with said bottom surface at their lower parts when infunctioning relation therewith to promote transmitting of coolingefllect from said surface to items in the upper part of saidcompartment, and means at the exterior of said structure for insulatingthe walls thereof from the surroundstructure is positioned in saidfunctioning relation, the exterior surface of said last-mentioned meansbeing in poor heat conducting relation with the spaced apart walls ofsaid structure.

WILHELM GEORG KOG-EL.

REFERENCES CITED The following references are of record in the ings insaid freezing compartment when said

